7. untar all the files onto the drive. The freebsd installation is simple, all it does is boots up a mini OS and runs a few shell scripts that do the untarring. All you'll have to do here is run them manually

Now, you need to export your installation directory so that the install.sh scripts will know where to untar the files.

Code:

# export DESTDIR=/mnt/install

Now run the 'install.sh' scripts in each of the directories. You will need to specify arguments for 'kernels/install.sh' and 'src/install.sh'. These arguments are quite self explanatory and explained when you run the script.
If you are really lazy you can do the following:

A manual ZFS setup is a tedious process without proper support in sysinstall, so I can see how mfsBSD can be useful (zfsinstall script).
But for simple UFS setups I prefer a manual livefs way. It's more fun.